A study of language development and defect in dyslexics and their relatives. The hypothesis is that one group of dyslexics is characterized by language difficulties. A set of tasks testing phonological, lexical and syntactical abilities has been developed and was administered to 48 dyslexic boys and 48 matched normal readers in grades 7 through 12. These tests will be used in working with the relatives of the dyslexics. A follow-up of dyslexic boys. We have reading, spelling, IQ, and other records of men who attended the Gow School 10 to 40 years ago. Gow is a school for dyslexic boys. We intend to test a sample of such alumni, selected on the basis of reading and spelling skills while at the school, as well as later educational attainment, family history, occupational career, and current attitudes to reading--all data which we have in hand as a result of a recent study. These data are now being analyzed and will be compared with data from an equivalent boys school attended by normal readers.